1. Field of the Invention
The present invention relates to the field of security alarm circuitry and apparatus. More particularly the present invention relates to the field of security alarm circuitry and apparatus for portable containers.
2. Description of Prior Art
Personal portable containers, such as briefcases and handbags, are widely used and carried. They often contain valuable personal items, such as passports, money, credit cards and jewelry. They also often contain important business documents, such as marketing plans, financial statements and profit reports. People cannot afford to lose their briefcases or handbags but in many instances these things are just striking targets for thieves. One way to protect the personal properties contained in such portable containers is to add locking devices for preventing unauthorized access to the container, such as the numerical locks used on briefcases. But once a locked briefcase is stolen by a thief and is in the possession of the thief, he is going to do everything he can to break the lock of the briefcase which can be easily accomplished. It would be best to prevent the briefcase from being stolen in the first place. It would be ideal if people can always hold their briefcases or handbags in their hand at all times. Unfortunately it is not always possible or convenient to do so. For example, at an airport ticket counter a businessman often puts his briefcase aside so he can free his hands to purchase an airplane ticket or do other things. A lady in a washroom sometimes puts her handbag on the counter when she is washing her hands or doing her make-up. It is quite common for these briefcases or handbags that are put aside even for a brief moment to be quickly stolen. It will be useful to have some sort of alarm apparatus attached to the briefcases, handbags and the like portable containers for protection against theft.
Many kinds of security alarm circuitry and apparatus have been introduced and manufactured for years. Typically a conventional security alarm circuitry and apparatus has the following essential components: a power unit for energizing the entire apparatus, which is usually an AC or a DC electrical power source; a switch unit for turning the apparatus on and off; a sensor unit for detecting the alarming situation, which may be a mechanical, electrical, thermal or optical sensing device; and an alarm unit for alerting the user if the alarming situation exists, which may be an auditory alarm or a visual alarm. Installing a security alarm circuitry and apparatus is a very effective way to prevent property losses caused by burglary. However, while there are numerous kinds of security alarm circuitry and apparatus available for properties such as buildings, automobiles, yachts and electronic equipment, there is no compact security alarm circuitry and apparatus available now which is specially designed, produced and used for portable containers such as briefcases and handbags to provide necessary protection against theft.